In recent years, there has been an active trend of digitalization of broadcasting, and fusion with communications has also progressed. In the field of communications, satellite digital broadcasting has already been started, and it is expected that terrestrial broadcasting will also be digitalized in the future. As a result of digitalization of broadcast contents, data broadcasting is also performed in addition to conventional video and audio. Products that realize the concept of storing television broadcasts on a hard disk and playing them back later (TV Anytime), such as TiVo (www.tivo.com) and ReplayTV (www.replaytv.com), are also on the market in the United States. Also, in the communications field, digital content distribution via the Internet has begun with music, and the number of Internet broadcasting stations that broadcast video is also increasing. In addition, access to Internet content has also been made possible for portable terminals through wideband access networks and connection to the Internet.
Amid such dramatic changes in information infrastructure, it is envisaged that henceforth it will become possible for users to easily access enormous information sources including video, audio, documents, and the like. Due to the fusion and digitalization of communications and broadcasting in this way, it has become difficult for users to handle enormous information sources without selectively transmitting and replaying only information that accords with the preferences of a user by using metadata that describes content. As shown in “Adapting Multimedia Internet Content For Universal Access” (IEEE Transactions on Multimedia, March 1999, pp.104-114), there have been proposed a description scheme for distributing one content to various terminals such as televisions and portable terminals, and accessing rich content on the Internet from an HHC (Hand Held Computer), PDA (Personal Digital Assistant), Smart Phone, or the like, and a method for converting (performing data adaptation of) Internet content according to the display capability of a terminal (for example, by changing the display size or number of display colors).
A conventional data adaptation apparatus will be described below. FIG. 68 shows a block diagram of a conventional data adaptation apparatus. A conventional data adaptation apparatus consists of a data adaptation section 100, a policy engine 101, a content analysis section 102, a content selection section 103, a content manipulation section 104, and a terminal 105. Internet content d1001 is input to the content analysis section 102. Terminal preferences d1002 that indicate terminal 105 performance information are stored in the terminal 105.
FIG. 69 is a detailed drawing of terminal preferences d1002. Terminal preferences d1002 contain screen color number information x and screen size information axb indicating the display capability of the terminal 105.
The operation of a data adaptation section configured as described above will be described below using FIG. 70. FIG. 70 is processing flowchart that describes the operation of the data adaptation section 100.
The policy engine 101 identifies the display screen size and number of display colors as the terminal capability according to terminal preferences d1002 obtained from the terminal 105 (P1201). The policy engine 101 then controls the content selection section 103 and content manipulation section 104 according to the information and policy identified in P1201.
The content analysis section 102 analyzes the physical data type of Internet content d1001 requested by the user (P1202). Then, the content selection section 103 judges whether display of the Internet content d1001 is possible with the display capability of the terminal 105 (P1203), and if the capability is sufficient to display the Internet content d1001, selects only content that can be displayed with the terminal capability from the Internet content d1001 (P1204).
Then, the content manipulation section 104 further converts the displayable content selected in P1204 to a form that can be displayed with the terminal capability. Specifically, the content selection section 103 judges whether the content is larger than the display screen size (P1205), and content larger than the display screen size is reduced in size by the content manipulation section 104 (P1206). If the content is not larger than the display screen size, the content manipulation section 104 judges whether the content is smaller than the display capability (P1207), and small content is enlarged by the content manipulation section 104 (P1208).
The content manipulation section 104 also judges whether the number of display colors of the terminal 105 are colors (P1209). Then, if the number of display colors of the terminal 105 are not colors, the content manipulation section 104 judges whether they are gray-scale (P1210), and if they are gray-scale, converts the content number of colors to gray-scale (P1211), and if they are neither colors nor gray-scale, performs binary conversion (P1212).
However, with the above-described conventional technology, a general policy is carried out-that is, selection and manipulation of content based on the result of content analysis in accordance with a policy suited to a specific terminal. Consequently, there is a problem in that it is only possible to perform data adaptation according to a predetermined fixed number of terminal patterns.
Also, with the conventional technology, it is not possible to perform selection and manipulation of content according to the preferences of the user: for example, selection and manipulation to display part of an image rather than reducing it in size. Therefore, with the conventional technology, even in a case where content selection and manipulation are performed using a predetermined specific terminal, there is a problem in that the user cannot perform data adaptation of content in a form according to his or her preferences using that terminal.